1. Field of the Invention
This invention generally relates to a front derailleur that is fastened to the bicycle frame. More specifically, the present invention relates to a front derailleur having a support member for mounting the front derailleur to a bicycle frame in a manner such that the angular position of the front derailleur can be finely adjusted relative to the bicycle frame.
2. Background Information
Generally, a front derailleur is mounted to the bicycle frame adjacent to the front chain rings to shift a chain laterally between the front chain rings. A front derailleur includes a fixed or base member that is non-movably secured to the bicycle frame. A front derailleur further includes a movable member or chain guide that is movably supported relative to the fixed member such that the chain guide moves between at least two lateral shift positions to shift the chain between the front chain rings. Typically, a linkage assembly is coupled between the fixed member and the chain guide in order to movably support the chain guide. The chain guide typically has a pair of cage plates or guide plates arranged to selectively contact and move the chain between the front chain rings. The cage plates or guide plates form lateral sides of a chain cage portion of the chain guide.
A front derailleur is sometimes attached to the seat tube (tubular member) of the bicycle frame by a mounting fixture, which is fastened by being welded or screwed to the seat tube of the frame. This mounting fixture is sometimes called a direct-mount type of a mounting fixture. Since such mounting fixtures are fastened to the seat tube before attaching the front derailleur to the frame, the orientation of the chain guide of the front derailleur is determined based on the mounting position of the mounting fixture. As a result, sometimes the chain guide or movable member of the derailleur will not be disposed in a parallel position directly above the front chain rings.